Electric switch



July 18, 1933. w. B. CHURCHER ELECTRIC SWITCH Filed Jan. 7, 1931 3 Sheets-Sheet 2 Ffglfi- 90 94 424 INVENTOR July 18, 1933. w B CH CHER 1,918,798

L35 o /32 l43 INVENTOR Patented July 18, 1933 U ITE STATES 1 ,918,798 PATENT orr ce wmrnr n. crmacnna, or BALTIIQBE, mnam), assrenoa 'ro 'r rinemnn L. nan-rm comm, or nan-moan, .mrmmn, a CORPORATION or IABYLAND merino swrrcn Application filed Ianuary 7,.1981. Serial No. 507,257.

My invention relatesfto solenoid switches and to systems which they are particularly well adapted to control from a remote locaand engine starting comprise the major portions.

1 The utilityof highwattag'e electrical lamps directly associated with aircraft and usually mounted at locations adjacent remotely located engines is of considerable importance and has introduced problems of installation and operation which are efiectively solved by the invention as herein set forth.

High powered lighting involves theuse of lamp filaments possessing considerable mass and inherent temperature characteristics which involve overloads of considerable magnitude for a period of time suflicient to heat the filament to a normal operating temperature. The filament -characteristics during normal operation are such as to re quire the maintenance of a potential which will operate the lamp at a high degree pf efficiency. Electric starters possess somewhat similar overload characteristics to those of electric lamps butthey are intensified by inductive characteristics which become evident at the moment of breaking the circuit.

The volts-amperes candle power characteristics of incandescent lamps and the characteristics of starting motors make it imrative "to minimize the potential losses throughout the system and at the same time to conserve weight in accomplishing the objective. The herein described system which includes my solenoid switches utilizes the electric starter cables for the alternative duty of operating high candle power lamps to thus eliminate a. considerable portion of the independent conductors and associated weights refluired for the system as heretofore insta ed upon aircraft. M double throw 1; I of solenoid switch is-e ective in preventing the simultaneous operation of the electric starter and the landing lamps on one pair of conductors which, due to weight conservation, are limited in current carrying capacity to a value which is adapted to 0 rate one or the other equipment at an eligitive potential.

Installations of storage batteries, generators, electric starting-motors, electric landing lamps, radio, electrically driven pumps, etc.,

upon aircraft are typical examples wherein it is imperatively necessary to provide switching equipment and circuits that are highly effective, eflicient, safe, reliable, of light weight, and can be serviced by average personne v v I illustrate and describe typical systems wherein my solenoid switches play an important part in meeting the objectives which are enumerated as follows:

One of the objects is to effectively control the operation of low potential high candlepower electric landing lamps, an electric starting motor, etc., from a remote location.

Another object is to provide a double throw switch which is Particularly well adapted to selectively control two lowpotential powercircuits from a remote location. Another ob ect is'to provide a switch in which the electrical contacting members and associated electrically alive parts are inherentl enclosed against the entrance of exp osive gases.

. Another object is to provide an interlockmg switch for guarding two circuits against simultaneous operation. a

Another object is to more efiiciently utilize the electrical conductors heretofore required only for short periods of time when operating an aircraft engine starter of the electric yp Another object is to reduce the number of heavy duty switches heretofore required for controlling landing lamps and electric motors associated with aircraft. 7

Another object is to eliminate the necessity of mounting highcapacity switches ufim an aircraft instrument board and the installation of heavy gauge conductors thereto.

Another object is to eliminate theproximity of high amperage to a compass mounted adjacent an aircraft instrument board.

Another object is to simplify the installafF' .16. A45 0 1g described in the specification are shown in operative relation.

Fig. 2 is a phantom view of a portion of Fig. 1 and including a schematic wiring diagram illustrative of a certain deviation from i 21. Fig. 3 is a plan view of my remotely controllable secondary switch. I

Fig. 4 isa side elevation of Fig. 3. Fig. 5 is a side view of the cover removed from Fig. 4. I

Fig. 6 is a plan view similar to Fig. 3 but with the cover removed.

Fig. -7 is a top plan view of a contact member having a tapered seat.

' Fig. 8 is a section at AA of Fig. 7. Fig. 9 is a top plan view of a contact member having a cross-slotted tapered seat.

I Fig. 10'is asection at B--B of Fig. 9.

Fig. 11 is a bottom plan view of a contact member having a spherical seat.

Fig. 12 is a section at GG of Fig. 11. Fig. 13 is a bottom plan view of a contact I member having a cross-slotted spherical seat.

Fig. 14 is a section through -D- D of Fig. 13.

ig. 15 is a section through a portion of Fig. 6 at EE showing the details of a solenoid terminal post.

Fig. 16 is a side elevation of the coniform contactor and core shown in Fig. 6.

' Fig. 17 is a plan view of the contactor end Fig. 18 is a section through FF of Fig. 6 showingthe relation of the interior parts to one another, contacts in open relation.

Fig. 19 is a portion of Fig. 1-8 when the contacts are inclosed relation.

Fig. 20 is a section corresponding to GG of a switch similar to that of Figs. 6 and 18 and showing the cover with the attached contactor stop member of either switch in relation to the contactor when'the solenoid is deenergized; certain modifications in details from Fig. 18 which adapt it toinverted mounting and to variable conditions encountered in aircraft service; and co-operative means for attaching lead-in conduits and enclosing the electrically alive parts of the switch.

"Fig. 21 is a plan view of either end of my double throw solenoid switch.

Fig. 22 is a side elevation of Fig. 21.

Fig. 23 is an interior plan view of an end cover when removed from Fig. 22.

Fig. 24 is a section HH of Fig. 22 when the electrical contacts are in open relation to one another.

Fig. 25 is a section similar to Fig. 24 when a companion set of electrical contacts are nested together.

- Fig. 26 is an elevation of the core and coniform contactors included in Figs. 24 and 25.

Fig. 6 serves as an interior plan view of either end of Fig. 22.

Fig. 17 serves as a plan view of either end of Fig. 26.

The drawings are described in detail as follows:

Fig. 1 illustrates a flying boat type of airplane which is equipped with high candle power electric landing lamps and electric starters cooperatively and selectively controlled by my double throw solenoid switch connected to one pair of main conductors. A hull is indicated at 35; port and starboard wings 3637 electric landing lamps 38-39; nacelle mounted engines 4041; electric motors 42-43 for starting the respective engines; my double throw solenoid switches44 45; remote control switches 46-474849; a source of electrical energy 50; electrical conductors 51-68 inclusive. Remote control switches 46 and 48 are shown, one in the hull and one in the nacelle, but in certain types of airplanes it is desirable to mount them adjacent each other as shown at 47 and 49.

Fig. 2 illustrates a nacelle mounted engine similar to 40-41 of Fig. 1 but showing a modification of the system wherein my single throw type of solenoid switch is subs'tituted for my double throw type and the starting motor is independently controlled in a conventional manner. A starting motor'is shown at 71; a conventional starting switch at 72; my single throw solenoid switch at 73; electrical conductors at 747 5 and by certain numerals corresponding to the port side of Fig. 1.

Figs. 1 and 2 illustrate typical uses for my solenoid switches but they are not intended to indicate that their usefulness is confined to aircraft lighting and engine starting systems. Certain other classes of electrical equipment can be controlled from one pair of main conductors to thereby save weight, cost of installation, and to guard against overloading of the electrical equipment.

Figs. 3' and 4 together with the accompanying details correspond to my single throw solenoid switch 73 which is schematically shown in Fig. 2. A removable cover 80 isshown attached by screws 81 to interiorly located clips attached to extension 82 of shell 83. Extension 82is provided with suitable holes 84 which are adapted to entrance and attachwith the single contact surface of the respecment of conduit encased electrical conductors as shown in a later figure.

A bracket 85 can be attached by screws-86 to shell 83 for convenient mounting of the 5 switch to a supporting structure.

Fig. 5 illustrates cover 80 removed from Fig. 4. A contactor stop member 87 is attached to cover 80 for a purpose hereinafter described.

Fig. 6 illustrates the contactor, contact members, and associated parts located within the chamber from which cover 80 has been removed. A composite plate fabricated from insulating material is shown at 88 and fastact member 91, and a companion contact member 92 having a slot 93, are attached by suitablemeans to plate 88 in coaxial relation to contactor 94, Contact members 91-92 are provided with terminal screws 95-96 for attachment of lead-in electrical conductors shown in a later figure. Two terminal posts nuts 97-98 are mounted upon plate 88 and are adapted to attachment of conductors leading from a source of electricity to a solenoid located beneath, plate 88.

Figs. 7 and 8, 9 and 10, illustrate in detail the formation of taper seat companion contact members 91-92 respectively. 1

Figs. 11 and 12, 13 and 14, illustrate in detail the formation of contact members 99- 100 that are similar to 91-92 but differ therefrom in that spherical seats are substituted for tapered seats. Members 91-92, 99-100 are preferably fabricated from ametal which possesses a high degree of conductivity. The contact areas of me ms 92 and 100 are slotted at 93 to thereby provide two contacting portions on either member and together tive companion members 91 or 99 three surfaces are provided uponwhich a surface of companion contactor 94 is adaptedto make intimately nested electrical connections when they are mounted and ground together in operating relation.

Fig. 15 illustratesthe details of a preferred construction of solenoid terminal posts inwhich a screw 101 has a square head 102 embedded in insulating plates 88 and retained therein by a nut 103 and lock washers .104. A hole is drilled through the length of screw 101 through which an end 105 of a solenoid is threaded and soldered to the outer end of the screw. The square head prevents turning of the screw and breakage of the attached wire. -A bushing is shown. at

106 to insulate screw 101 from the adjacent metal.

. Figs. 16 and 17 illustrate a core type armature 107 having a truncated contactor attached thereto at one end.- The armature is fabricated from magnetizable metal. Contactor 94 is preferably fabricated from a tened to shell 83 .at 89. Clips for fastening the cover to shell 80 are shown at 90. A confunctions of which are hereinafter described.

Fig. 18 is a section through F-F of. Fig. 6

after removal of cover 80 to illustrate the interior details of-the switch which is schematically indicated at 73 in Fig. 2. The con ,tactor is shown in open relation to the com-- panion contactmembers. The core is universally movablewithina tube 110 which is preferabl fabricated from an insulating material. t 111 a compression spring is shown in a relation to armature 107 and shell- 83 wherein the electrical connections between 91-92, and 94 are broken. At 112 an insula tor is shown which prevents electrical connection between spring 111 and shell 83. At

113 is shown in section the turns of electrical conductors comprising a solenoid mounted upon tube 110 and insulated at 114-115-116 from the adjacent metal parts. The two ends of solenoid 113 are connected to terminals 97-98 the details of which have been described. Amagnetizable ring 117 is coaxially mounted in relation to tube 110 and serves as a portion of the magnetic circuit comprising shell 83 and core 107. Member 117 also serves as a supporting member for plate 88 upon which contact members 91-92 are fastened. Replacement of cover 80 to the position shown in Fig. 4 forces stop member 87 against the spring biased armature contactor. The length of 87 15 such as to leave an ample opening between contact members 91-92 and contactor 94 in response to spring 111 when solenoid 113 is de-energized.

Fig. 19 is a portion of section F-F of Fig. 6 when contactor 94 is nested with contact members 91-92.

Due to contact member 91 having one seat to contact member 92 having two seats separated from each other by slot 93; and to their coaxially mounted relation to solenoid 113 and contactor 94,. the latter is adapted to nest in concentric alignment with the contact members to thereby provide. triple faced, high ampere capacity, and highly etlicient electrical connections therebetween. The relation of the contacting surfaces to one another provides a construction whereby they can be accurately ground together by revolving the armature and contactor with a tool applied at slot 108 without dismantling the switch or removing it from the circuit noid 113 causes a sliding action between the contacting surfaces of the contactor and the contact members thus tending to burnish them when the solenoid is energized. The

armature core, together with attached con tactor, are free to revolve more or less during successive energization of the solenoid to thereby equalize the wear on the contacting surfaces.

Fig. 20 illustrates certain modifications in design from Fig. 18 and in which, due to a re versed mounting from that of Fig. 4, spring 111 can be omitted in favor of gravitational opening of the contacts. The construction shown in Fig.18 is adapted for use in connection with apparatuswhich is subject to inversion whereas that of Fig. 20 is adapted to mounting in the vertical position as shown. Shell 120 performs the same magnetic function as does 83 in Fig. 18 and can be provided with a magnetic'core portion 121. An extended collar portion 122 is shown in detachable relation to the shell for convenience in manufacture and to meet variable conditions encountered in the installation of conduit encased lead-in electrical conductors as typically indicated at 123. Chamber 124 provides for enclosure of the contacting members against the entrance of explosive gases and their subsequent ignition by sparks at the contacts when the switch is operated.

The contactor shown in Fig. 18 at 94 is provided with a tapered surfacewith which contact members 91-92 are adapted to nest, and the contactor shown in Fig. 20 at 125 has a seat comprising a double curvature surface with which companion contact members 99-100 are adapted to nest, when the solenoid is energized. Either of the formations in companion relation is effective in the attainment of eflicient electrical connections.

.The detail construction of my double throw switch will now be described:

In Figs. 21 to 25, covers 130-130 are'provided with. resiliently controlled stop members 131-131. The stop members are fabricated from an insulating material and are retained in housings 132-132 by shoulders 133-133. Springs 134-134 normally restrain" the stop members to the positions shown in Fig. 24. Shell 135 is fabricated from a magnetizable material and functions in the same manner as do shells 83 and 120 in the types of single throw switches heretofore described. Extensions 136-136 are provided for attachment of covers 130-130 and to provide chambers 137-137. Two solenoids 138-139 are mounted within shell 135 and are connected respectively to terminal posts which are located within the cham bers as typically shown at 97-98 in Fig. 6. Solenoid .139 is connected to a pair of terminal posts 97-98 in chamber 137 which correspond to terminal posts 97-98 in chamber 124 of Fig. 6. Solenoid 138 is connected to similar posts, conveniently referred to as 97'-.98', located in chamber 137. A magnetizable member'l40 magnetically separates the solenoids from each other and is insulated therefrom at 141. A core of magnetizable material 142, Fig. 26, is located within solenoids 138-139 and is normally restrained nections of the solenoids to the source of.

controlled electrical energy as shown in Fig. 1 can be such as to magnetically polarize member 140-in'relation to core 142. Energization of solenoid 138 will attract the core against the tension of spring 134' thereby closing the electrical circuit between contactor 143 and contact members 91-92 as shown in- Fig. 25. Energization of solenoid 139 will attract the core in the opposite direction against the tension of-sprin 134 to thereby close the electrical circuit etween contactor 143 and contact members 91'-92. Energization of both solenoids simultaneously can close but one set of contacts and thereby prevents simultaneous operation of units connected to the circuits represented by 91- 92, 9192'.

The operation of the switches and the units which they control will now be described:

Referring to Fig. 1, landing lamp 38, engine starting motor 42, and double throw remote control switch 44, located on the port side of the airplane, are under remote control by switch 46 located for convenient operation by the pilot and by switch 48 remotely located from the pilot. Starting motor 42 can be operated by closin switch 48 to thereb energize one of theso enoids associated wit 1 switch 44. In the event that switch 46 be closed to the companion solenoid of switch 44, the circuit to landing lamp 38 remains open until switch 48 is opened to permit the contactor of switch 44 to open the circuit to motor 42 and to close the circuit to lamp 38. Lamp 38, motor 42, and switch 44, located on the port side of the airplane, correspond to 39, 43 and 45 on the starboard side. Switch 45 is controllable by switches 47-49 located for convenient operation by the pilot. Switch 44 is shown in position to operate motor 42 and to prevent operation of lamp 38. Switch 45 is shown in position to operate lamp 39 and to prevent operation of motor 43.

The circuit lock-out feature of switches 44-45 prevents overloading of cables 53-55 or 54-56, in the event that an attempt is made to operate lamp 38 and motor 42, or 39-43, simultaneously by closing switches 46-48, or 47-49. Conductors of less weight can be used than when allowance tery 50,- may make it necessary mustbe made for overloading caused by simultaneous operation of a motor and a lamp, and for loss in operating potential. Also, limitations in weight of a source of electrical energy, conveniently represented by a batto guard against overloading caused by the simultaneous operation of connected mechamsm which is intended for intermittent use.

- sociated with cumbersome equipment on the conservation of po .761,

.high current density.

are remotely controlled by a instrument board and utilizes the starting motor cables for the double duty of engine starting and the operation of landing lights.

The single throw and-the double throw switches herein illustrated and described follow the same general construction and are thereby well adapted to the economical production of either unit as governed b conditions of installation or operation. T e coniform types of contactor produce and main tain a highly efficient electrical connection between the contacting surfaces of the companion contact members and therefore are particularly well adapted for use in low potential systems which involve comparatively I have illustrated two types of aircraft electrical systems, one in which high powered electric landing lamps are operably connected to extensions of the cables ordinarily used for the engine starting motor and single throw solenoid switch which is controlled by a small switch mounted on the pilots instrument board; and one in which high powered landing lamps and a starting motor are selectively operable by a double throw solenoid switch which is controlled by two small switches located for convenient operation but, due to the cooperative relation between the solenoid switch armature and the two solenoids, simultaneous operation of the starter and lighting units is prevented.

A situation which is similar to the one abo e described arises in the operation of an electric generator to furnish the power for radio and for operation of accessories, pumps for example. Economy in weight,

and safety of the electrical installation, requires assurance that such equipment as is intended for intermittent operation by the generator shall be guarded against simultaneous connection therewith.

The systems as described are intended to indicate typical installations whlerein 'my solenoid switches are highly effective in the attainment of the enumerated objectives and other uses will become apparent to those skilled .in the art.

I claim:

1. An electric switch including in operative relation: a conical contactor; a plurality of non-resilient segmental contact members each having a coniform seat that is adapted to concentrically nest with said contactor in coextensive surface contacting relation; means to nest said contactor with said seats in said concentric relation; means. to separate said contactor from said seats; and a stop member to limit the separation between said contactor and said seats.

2. An electric switch including in operative relation 2 a conical contactor; a plurality of non-resilient segmental contact members each having a coniform seat that is adapted to concentrically nest with said contactor in coextensive surface contacting relation; means associated with said contactor to facilitate surfacing said seats intointimate electric contacting relation; means to nest said contactor with said seats in said concentric relation and means to separate saidcontactor from said seats.

3. An electric switch including in operative relation: a conical contactor; a plurality of non-resilient segmental contact members each having a coniform seat, said seats being formed to surfaces of double curvature and thereby adapted to both radially and concentrically nest with said contactor in coextensive surface contacting relation; means associated with said contactor to facilitate surrelation: a conical contactor; a pair of non-f resilient segmental contact members each having a coniform seat, one of said seats being transversely slotted, said seats being formed to surfaces of double curvature and thereby adapted to both radially and concentrically nest with said contactor in coextensive triple surface contacting relation; means associated with said contactor to facilitate surfacing said seats into intimate electric .relation; means to nest said contactor with said seats; and means to separate said contactor from said seats.

5. An electric switch including in operative relation: a conical contactor; a pair of non resilient segmental contact members each having a coniform seat, one of said seats being transversely slotted, said seats being adapted to nest with the surface of said contactor in coextensive triple surface contacting relation; means to nest sald contactor with said seats; means to separate said contactor from said seats; and a stop member to limit the separation between said contactor and said seats.

6. An electric switch includingin operative relation: a conical contactor; a pair of nonresilient segmental contact members each having a coniform seat, one of said seats being transversely slotted, said seats being adapted to nest with said contactor in coextensive triple surface contacting relation; means to nest said contactor with said seats; said means comprising a core type armature and a solenoid, said armature being connected to said contactor and said solenoid being coaxially mounted in relation to said armature; means to separate said contactor from said seats when said solenoid is de-energized; and a stop member to limit the separation between said contactor and said seats.

7. A double throw electric switch including in operative relation: a pair of conical contactors; a pair ofnon-resilient segmented contact members for each of said contactors, each of the members having a coniform seat that is adapt-ed to nest with one of said contactors in coextensive surface contacting relation; means to nest either of said contactors with a pair of said contact members, said means including a core type armature to which said contactors are attached, said armature having a non 'magnetic'portion, and a pair of solenoids, said solenoids being mounted in relation to the coaxially magnetic portionof said armature; means intermediate said contactors and the ends of said armature to guide said core within the solenoid and to provide for pendulous movement of both contactors in a plurality of angularly related planes while seating with a companion pair of contact members in response to either one of said solenoids being energized; means to separate both contactors from the respective contact members and to centralize said core in relation to said solenoids when said solenoids are de-energized, said means comprising a resiliently controlled stop member adjacent to each of said contactors, the movement of said stop member being limited; a housing for said armature, contactors, contact members, and solenoids; a removable cover for each end of said housing adjacent said contactors; and said stop members being mounted upon said covers in operative relation to said contactors. i j

8. An electrical switohiincluding in operative relation, a tube of magnetizable metal two solenoids, said solenoids being mounted interiorly of said tube in concentric relation and in coaxial relation to each other; a core type armature common to and insulated from said solenoids; two coniform contactors attached one to each end of said armature in coaxial relation; a plurality of contact members mounted in insulated coaxial relation to each of said contactors and adapted to nest therewith when said solenoids are selectively energized; resiliently controlled stops to longitudinally centralize said armature in a relation to said solenoids wherein said contactors are separated from said contact members when said solenoids are de-energizcd; an extension to each end of said tube; a cover for each of said extensions; said extensions and said covers being adapted to enclose said contactors and said members.

9. An electric switch including in operative relation: a conical contactor; a pair of non-resilient segmental contact members each having a coniform seat, one of said seats being transversely slotted, said seats being adapted to nest with said contactor in coextensive triple surface contacting relation; means to nest said contactor with said seats: said means comprising a core type armature and nsolenoid, said armature being connected to said contactor and said solenoid being coaxially mounted in relation to said armature; means adjacent the end of said armature rcmote from said contactor to longitudinally guide the core within the solenoid and to provide for pendulous movement of the contactor in a plurality of planes while seating with said contact members; means to separate said contactor from said seats when said solenoid is de-energized; and a stop member to limit the separation between said contactor and said seats.

10. An electric switch including in operative relation: a conical contactor; a pair of non-resilient segmental contact members having a coniform seat, one of said seats being transversely slotted, said seats being adapted to nest with said contactor in coextensive triple surface contacting relation; means to nest said contactor with said seats, said means comprising a core type armature and a solenoid, said armature being connected to said contactor, and said solenoid being coaXia-lly mounted in relation to said armature; means adjacent the end of said armature remote from said contactor to longitudinally guide the core within the solenoid and to provide for pendulous movement of the contactor in a plurality of planes while seating with said contact members; means to separate said contactor from said seats when said solenoid is de-energized; a stop memberto limit the separation between said contactor and said seats; a housing for said contactor and armature, said contact members, and said solenoid; a movable cover for said bollsing, said stop member being attached to said cover adjacent to said contactor.

WILLIAM B. CHURCHER. 

